Bad debts resulting from changes of business tenancies, some fraudulent, will increase following the scaling back of government support for non-domestic customers, Energy UK (EUK) has warned Ofgem. In its submission to the energy regulator’s recently closed call for input on the non-domestic gas and electricity market, the sector’s umbrella body raises concerns that changes of tenancy or occupier (COT) can be a "very significant cause of bad debt" for suppliers.